The present application relates to a method for preparing acylated aminoanthraquinone dyes.
U.S. Pat. No. 3,719,489 describes and claims photographic processes employing certain photographically inert compounds which are capable of undergoing cleavage in the presence of the imagewise distribution of silver ions made available during processing of a silver halide emulsion to liberate a reagent, such as, a photographically active reagent or a dye in an imagewise distribution corresponding to that of said silver ions. In one embodiment disclosed therein, color images are produced by using as the photographically inert compounds, color providing compounds which are substantially non-diffusible in the photographic processing composition but capable of undergoing cleavage in the presence of the imagewise distribution of silver ions and/or soluble silver complex made available in the undeveloped and partially developed areas of a silver halide emulsion as a function of development to liberate a more mobile and diffusible color-providing moiety in an imagewise distribution corresponding to the imagewise distribution of said ions and/or said complex. The subsequent formation of a color image is the result of the differential in diffusibility between the parent compound and liberated color-providing moiety whereby the imagewise distribution of the more diffusible color-providing moiety released in the undeveloped and partially developed areas is free to transfer.
Copending application Ser. No. 644,915, filed on even date herewith discloses photographic process for forming a dye image from a substantially colorless precursor which comprises a dye having at least one formylated amino group and which also includes a moiety containing a thiazolidin-2-yl group which upon silver-assisted cleavage initiates a reaction sequence leading to the formation of the image dye. The present application is directed to a method for preparing acylated aminoanthraquinone compounds. The compounds prepared by this method include formylated aminoanthraquinones which are useful as intermediates in the preparation of image dye-providing material suitable for use in such photographic applications.